Are you the person who drives over to the gym, parks, realizes you forgot your headphones, and immediately drives home to get them because you can’t workout without them? You’re not alone, and perhaps more importantly, science is on your side. A University of Edinburgh study on the effects of music and workout playlists found that not only does the right kind of music help boost your efforts when jogging outside or on the treadmill, but they also found the ultimate motivational workout song.

According to the study, the song “Eye of the Tiger” by Survivor got the most effort from fatigue participants compared to other songs that were selected. Anecdotally, this track has been on workout/motivational playlists and mixes on Walkmans to Discmans to iPods to smartphones as a multi-generational favorite, especially for marathon runners. Which is why it shouldn’t be a surprise that the song has over 1.6 billion streams on Spotify and its official music video has 1.1 billion views on YouTube.

Another music study by Dr. Jacob Jolij found that “Eye of the Tiger” was also one of the most feel-good songs of all time. At 109 beats per minute, the song hits that sweet spot between upbeat and motivational, which rewards our brains’ preference for repetitive rhythmic structure creating a consistent drip of pleasing dopamine. This feel-good neurotransmitter can make you feel good as you’re working out while also motivating you to continue, creating a feedback loop of encouraging effort and rewarding you for that effort as you commit to your task. Being that the song scientifically both motivates and rewards a person chemically through its lyrics, riffs, rhythm, and beat, one can conclude that it’s the most motivational song of all time.

The history of the song is burned into American popular culture. After Sylvester Stallone was denied the rights to use “Another One Bites the Dust” by Queen as the theme song for the movie Rocky III, he approached Survivor to come up with a song specifically for the film. After viewing footage of the movie, the band recorded a demo on February 1, 1982 and sent it to Stallone. Sly liked it so much he didn’t wait for a re-recording in a professional studio and immediately added the demo version to the film. A recut, professional release of “Eye of the Tiger” was unleashed to the masses three weeks after Rocky III hit theaters, and it has been on a wild run on and off ever since.

Music is a great motivator in not just exercise, but when you’re preparing, working, cleaning, or doing some other task. Studies and articles from the National Institute of Health and Harvard Business Review back this up. The right kind of music can help not only motivate a person to keep going at their task, but could keep them focused and boost overall productivity along with performance. Other studies show that listening to music alters our perception of time, making long and boring slogs or duties feel shorter depending on if we’re listening to the right track. So, it might be worth putting on your headphones not just when you’re on the treadmill, but also if you’re studying for a test for extra focus, cleaning your house to make the next three hours feel like 30 minutes, or if you need that extra motivational brain boost before a speaking engagement.

So what songs should you add to your motivational/boost/workout playlist aside from “Eye of the Tiger”? Well, that’s up to you. While many fitness instructors and health experts have their opinions and list songs ranging from artists like Aretha Franklin to Mastodon to DMX to Mariah Carey and back again, it’s still pretty much subjective. “Eye of the Tiger” might not even be the best track for you. Over time, listening, and investigating recommendations from friends and family, you’ll be able to curate a great playlist or multiple playlists specifically for when you need that extra “oomph” for a particular task. Enjoy the search.

  • How D.C.’s ‘humanure’ fertilizer creates lush gardens and big profits while improving the environment
    Photo credit: CanvaWhat you flush away could help your garden grow.

    The District of Columbia Water and Sewer Authority—now known as D.C. Water—has long provided water and sewer services to Washington, D.C. But for the past decade, the utility has also had an unexpected side hustle: turning human wastewater into fertilizer with flourishing results.

    At most wastewater treatment plants, flushed water is cleaned, while the remaining solid matter is hauled away for disposal. Over time, transporting and disposing of that waste can cost millions of dollars while increasing carbon emissions from the trucks carrying it. A decade ago, however, D.C. Water decided to invest in transforming the solid waste into “humanure” rather than throwing it away.

    Growin’ grass and makin’ gas

    At the end of the wastewater treatment process, the collected human waste solids are processed into biosolid fertilizer using technology developed by Norwegian company Cambi. The process doesn’t just produce high-quality fertilizer—it also generates biogas that can be put to good use.

    “So you get up to 40% more biogas,” Cambi CEO Eirik Fadnes said. “That biogas can be used to generate electricity to be used elsewhere in the wastewater-treatment plant or put on the grid and sold.”

    D.C. Water sells the biosolid fertilizer under the brand name Bloom, and it’s already proving to be a success. Bloom has been used throughout the Washington, D.C., area by customers including Catholic University, Mount Olivet Cemetery, and the Franciscan Monastery. It’s also used on numerous lawns, school grounds, community gardens, and golf courses.

    Success by the numbers

    The numbers underscore D.C. Water’s success. To date, nearly 400,000 tons of Bloom have been sold across Washington, D.C., Maryland, Pennsylvania, and Virginia, generating $13.6 million in revenue. D.C. Water originally estimated it would take 20 years for Bloom to pay off its investment. But thanks to strong demand from institutions, landscapers, and local garden centers, the utility is now on pace to recoup that investment in just 12 years.

    Bloom is also helping D.C. Water meet its environmental goals. By turning waste into a useful product instead of hauling it away for disposal, the utility has reduced its carbon footprint by roughly 50,000 metric tons of CO₂ emissions each year—the equivalent of taking more than 11,700 gas-powered cars off the road annually. The process also produces biogas, which can be converted into electricity to help offset the energy costs of wastewater treatment.

    Human waste works wonders

    None of this would matter if human biosolids weren’t effective at improving soil. “Humanure,” a term coined by Joseph Jenkins, refers to compost made from properly treated human waste. Because human feces can contain disease-causing pathogens, it must be handled carefully. After all, we call it “waste” for a reason.

    When human waste is composted correctly, naturally occurring microbes break down the organic material while generating enough heat to destroy harmful pathogens. Over time, the result is a nutrient-rich compost that can improve soil health. Some farmers even build specialized outdoor composting toilets to create humanure for use on their land.

    Should D.C. Water continue on this path of simultaneous profitability and environmental improvement, it’s likely other wastewater treatment plants will follow its lead.

  • A Spanish park has been free of wildfires for over a decade thanks to 18 donkeys
    Photo credit: CanvaDonkeys and other livestock could help prevent mass wildfires.

    According to NASA, wildfires have doubled worldwide due to climate change. Throughout the globe, governments and environmentalists have been trying to find ways to curb the fires. One particular national park in Spain has found a solution that has been keeping them fire-free for over a decade: donkeys.

    Since 2014, the Firefighting Donkey Battalion unit consisting of 18 donkeys has been preventing wildfires in Doñana National Park in Doñana, Spain. The mission these donkeys do is simple: eat the dry brush that usually sparks and fuels wildfires. The donkeys spend up to seven hours a day using their voracious appetites to graze and clear a 130 by 50 feet area of dried grass, scrub, and other vegetation.

    Why donkeys?

    While humans can do this type of clearing out of dry brush, using donkeys for this work is arguably more effective. While it is a slower process, it is consistent and thorough. Donkeys are able to quietly patrol in areas that are inaccessible to vehicles. In exchange for the feasting, the donkeys get about eight gallons of water and rest. No money or fuel needed.

    The donkeys’ bodies are also pretty much built for this kind of environmental work, too. Their stomachs are built to eat the same rough and dry grass repeatedly without issues. These daily grazings slowly but surely remove potential origin sources for fires. As a bonus, the donkeys are naturally disposing of the dried vegetation whereas humans would have to find a different way to dispose of it.

    Having donkeys or other livestock graze in such areas was once more common in agriculture prior to modern farming. Some argue that the machinization of farming and urbanization have reduced the number of grazing animals. This in turn allows more vegetation growth that become dry spots for more wildfires to occur.

    The method expands

    This method has been so successful that other areas of Spain have adopted it. In 2020, Tivissa launched the Burros Bomberos project with three donkeys to so much success they’ve expanded. They now have 40 donkeys grazing and clearing nearly 400 hectares of land.

    The Andrea Association in Allariz uses a team of donkeys to clear and maintain nearly 1,000 hectares of a biosphere reserve. Using GPS to monitor the donkeys’ activity, the group of grazers travel 19 kilometers per day to feed. Similar initiatives have since started in Basque Country, Catalonia, and Galicia, too.

    Other ways to combat wildfires

    In the United States, California has been using goats in a similar function. The group Fire Grazers Inc. has been contacted throughout California to bring hundreds of goats to eat dried vegetation. Much like donkeys, goats are built to eat rough and dry brush. This includes certain plants such as star thistle that are painful for human hands to grab.

    It’s important to note that donkeys or other animals that eat dry scrub are the primary solution to wildfires. The same folks behind these initiatives also advocate proper forest planning and land management. This includes reducing the amount of easily flammable species of plants and trees such as pine. It takes thought, care, work, and maybe a bunch of donkeys to make a difference.

  • Spanish zoo study suggests that giraffes can do basic math
    Photo credit: CanvaA study is showing giraffes could be using math.
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    Spanish zoo study suggests that giraffes can do basic math

    These hoofed mammals can understand addition.

    The results of an experiment done in a Barcelona zoo suggest that giraffes are capable of doing basic mathematics.

    A group of researchers from the University of Leipzig, the Max Planck Institute for Evolutionary Anthropology, and the University of Barcelona published their study observing four giraffes at the Barcelona Zoo. The experiment involved the giraffes observing containers that had different amounts of carrot pieces inside.

    How did this experiment work?

    The researchers showed each giraffe the two yellow containers and the amount of carrots within each one. After a few seconds, they closed the containers, keeping the carrots out of sight. They then showed each giraffe a green container which had extra carrots inside. Researchers took the carrot pieces from the green container and placed them into one of the closed yellow containers. They then let each giraffe independently choose which of the two closed yellow containers they preferred, without them seeing the total number of carrot pieces within each box.

    The results found the giraffes would choose the container that had the most carrot pieces around 68% of the time. This suggests to the scientists that the giraffes were mentally adding the carrots up in each container before making their choice. After all, there have been past studies suggesting that other hoofed mammals, such as horses, had similar capability of basic quantity tracking.

    The researchers did the experiment again. Only this time they subtracted the amount of carrots in each container. The giraffes were mostly unsuccessful at finding the container with the most pieces. So while giraffes showed signs of knowing addition, they don’t quite process all forms of arithmetic.

    Math = Survival

    Scientists believe that this understanding of addition helped giraffes survive in the wild. They cite that acacia trees, a dietary staple for wild giraffes, can be spread far apart in Africa. Being able to figure out which area has the most trees and the most leaves can help them decide where to graze next.

    Giraffes also live in flexible groups that often change in size. One grouping can mix in with another group and then branch off or away. This means that the giraffes often have to keep track of those currently within their group and surroundings to survive.

    Can other animals do math?

    Giraffes are just the latest animal species known to have some form of mathematical skill. Chimpanzees displayed similar abilities to count as giraffes in a similar experiment that involved them picking the bowl with the most chocolate pieces rather than carrots. Chickens and black bears also showed aptitude in quantity tracking, too. 

    Scientists theorize that most of the animals that can do this basic math through evolutionary survival. After all, the animal that can deduce where more food is tends to live longer.

    One species that displays remarkable mathematical ability are Tunisian desert ants. An observation of their navigational skills of finding their way to food and back to their nest suggests they use the sun as a compass in combination with mentally keeping track of the number of steps they take in a three-dimensional space. In short, these desert ants possess basic geometric and trigonometry skills.

    While you wouldn’t want wild animals to calculate your taxes, it’s interesting to see how rudimentary math is a language that goes beyond species.

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